This invention relates to a fire safety device and, more particularly, to apparatus for use therewith having fusible means attaching a magnet to one member for magnetically holding the one member to another member until heat melts the fusible material.
Many fire safety devices are well known. Sprinklers and fire doors are examples of fire safety devices with which the present invention has particular utility. A sprinkler will be used to illustrate the invention, it being understood from the outset that the invention may also be used with other fire safety devices such as, for example, the fire doors, a heat sensor, and a heat activated alarm signal.
Known sprinklers have a compound head assembly for discharging and dispersing a fire extinguishing agent supplied from a pipe coupled to the head assembly when heat from a fire opens a normally closed valve in the sprinkler head assembly. Such sprinklers often have a gear-like dispersing member in spaced alignment with the valve in the sprinkler for dispersing the extinguishing agent. This structure, although desirable for discharging and dispersing the fire extinguishing agent during the extraordinary conditions of a fire, also gives the sprinkler an unusual, protruding appearance. The usual placement of such sprinklers on ceilings or walls of a structure makes them conspicuous and their unusual appearance, therefore, undesirable.
The structure and the placement of the sprinklers also makes them difficult to clean. For example, the usual placement of the sprinklers makes it difficult to paint the adjacent ceiling or wall without also painting the sprinkler. Paint on the sprinkler may interfere with its operation. Cleaning paint from the sprinkler, however, is difficult both because of its compound structure and because of its placement. Cleaning the sprinkler also runs the risk of accidentally opening the valve for discharging the fire extinguishing agent. The agent then causes unnecessary water (or other fire extinguishing agent) damage to the structure.
Many specialized structures are intended to provide a highly clean, sterile environment for, for example, sensitive manufacturing processes or health care. It is often desired to wash such structures with dust-removing or disinfectant solutions. These solutions are difficult satisfactorily to apply to the compound structure of the sprinkler.
For all of these and other reasons, it is often desired to recess the sprinkler in the ceiling, wall, or other structure adjacent which it is mounted and cover the recessed sprinkler with an escutcheon. The escutcheon is desirably substantially flush and close-fitting with structure adjacent which the sprinkler is mounted. Although the escutcheon provides a neat appearance, and may be readily cleaned, disinfected, and freed of encumbering paint, means must still be provided for permitting the operation of the sprinkler during the extraordinary conditions of a fire.
One U.S. patent suggests an escutcheon which is entirely formed of fusible material such as solder. The heat of a fire is supposed to melt the escutcheon from the sprinkler and then activate the sprinkler. Another U.S. patent suggests attaching an escutcheon with coil springs extending to clips which are attached to the escutcheon by a fusible material. Heat from a fire is supposed to melt the fusible material to release the clips from the escutcheon and thereby permit the escutcheon to fall from the sprinkler.
Another safety device with which the present invention has particular utility is a fire safety door. Such doors often have a spring which tends to close the door. The spring is normally restrained from closing the door by an electromagnetic latch. During a fire, heat responsive means cut-off the electric power to the electromagnetic latch to release the spring for closing the door. If, however, the heat responsive means fails to cut-off the electric power or the electromagnetic device has acquired sufficient residual magnetization to continue to hold the door against the spring, the door will fail to close. It is therefore desirable to provide an additional safety device at each fire door which, under extraordinary heat at the door, will alternatively release the electromagnetic latch to permit the spring to close the door. It may be desired, of course, to also cover the door closing mechanism with an escutcheon.